1. Field of the Invention
The invention is directed to a clamping device, in particular for securing an axially displaceable rod in optional adjustment positions, in which the object or rod to be clamped is clamped by a rolling body supported at a housing enclosing it. It will be understood that, alternatively, in kinematic reversal, the clamping device could be disengaged and then displaced and secured relative to the object or rod. Such clamping devices serve, for example, to secure a tripod, supporting leg or the like support or holder or add-on part for devices, in particular musical percussion instruments, in optional attitudes and positions.
2. Description of the Related Art
Clamping devices on percussion instruments are exposed to considerable impactlike loading whether used to secure the position of legs which are adjustable in length or to hold instrument parts in a vertically adjustable manner, e.g., the movable cymbals of a high hat. Moreover, the natural vibrations of the instrument persist for a long time after a blow delivered to the clamping device. The parts connected by the clamping device must therefore be capable of being securely fastened in position relative to one another in order to prevent any change in position during playing which would require readjustment. DE-30 00 536 A1 describes a clamping device for securing optional adjustment positions of a holding member on percussion instruments which is guided on a bar or the like so as to be displaceable coaxially thereto, in particular for holding cymbals, high hats, drums, etc. so as to be vertically adjustable. This holding member has a chamber with opposing inclined walls which encloses the bar and narrows in diameter in the direction of load. The rolling bodies which produce the clamping action and have at least cylindrical portions are arranged between the inner wall of the chamber and the bar. The central region of the rolling bodies is adapted to the profile shape of the bar which can have, e.g., a round, hexagonal or octagonal cross section. An adjusting screw which can be screwed into the housing and is provided with a knurled head acts on a plate arranged above the rollers and a lower plate arranged below the rollers is supported on a pressure spring.